Method of photodynamic therapy (PDT) for bladder cancer

ABSTRACT

This invention relates to a method of photodynamic therapy (PDT) for bladder cancer and its use as an adjuvant or neoadjuvant therapy in the treatment of bladder cancer. The invention provides a composition comprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable salt thereof for use in a method of photodynamic therapy for bladder cancer, wherein said composition is instilled into the bladder of a patient in need of such treatment and the inside of said bladder is exposed to blue light having a fluence rate of 1.5 to 12.5 mW/cm2.

This invention relates to a method of photodynamic therapy (PDT) forbladder cancer and its use as an adjuvant or neoadjuvant therapy in thetreatment of bladder cancer.

Bladder cancer is the ninth most common cancer diagnosis worldwide, withmore than 330 000 new cases each year and more than 130 000 deaths peryear. At any point in time, 2.7 million people have a history of urinarybladder cancer.

The diagnosis of bladder cancer ultimately depends on cystoscopicexamination of the bladder (cystoscopy) and histological evaluation ofthe resected tissue. In general, cystoscopy is initially performed inthe office, using flexible instruments. At the initial diagnosis ofbladder cancer, 70% of cases are diagnosed as non-muscle-invasivebladder cancer (NMIBC) and approximately 30% as muscle-invasive bladdercancer (MIBC).

If a bladder tumor has been detected during cystoscopy, the patient willundergo transurethral resection (TUR), i.e. a procedure where thebladder is visualized through the urethra and tumors and lesions areresected. In case of NMIBC, such a resection is to completely remove thetumor. In case of MIBC, such a resection is of a palliative nature.Apart from the resection of the tumor, the TUR is also carried out toenable a correct histological diagnosis of the bladder cancer by apathologist based on examination of the resected tumor/tumor biopsies.

As a standard procedure, cystoscopy and TUR are performed using whitelight. However, since the use of white light can lead to missing lesionsthat are present but not visible, photodynamic diagnosis (PDD) is oftenused in such procedures. In general, PDD involves the administration ofa photosensitizer or a precursor thereof (i.e. a “photosensitizingagent”) to an area of interest. The photosensitizer or precursor thereofis taken up into the cells, where a precursor of a photosensitizer isconverted into an active photosensitizer. Upon exposure of the area ofinterest to light of a suitable wavelength, the photosensitizer isexcited and, upon relaxation to its ground state, fluorescence occurs,which is detected.

Hexyl 5-ALA ester (hexaminolevulinate, HAL) and its salts are suchphotosensitizing agents. HAL preferably penetrates rapidly proliferatingcells, e.g. tumor cells, where it is converted into porphyrins, such asprotoporphyrin IX (PpIX), which are photosensitizers and fluorescentcompounds. Under subsequent blue-light illumination, the porphyrins emitred light and thus enable specific and accurate visualization of thetumor. Hexvix®, in the US and Canada Cysview®, (Photocure ASA/PhotocureInc/Ipsen SA) is a commercially available approved diagnostic agent thatcomprises HAL. As an adjunct to white light, Hexvix® is used togetherwith blue light in the photodynamic detection of bladder cancer duringcystoscopy and TUR procedures, see e.g. Cysview®, Highlights ofPrescribing Information, 2011). Such photodynamic detection has becomean important part of the overall management of bladder cancer, i.e.diagnosis and treatment of this condition (see e.g. Thomas et al.,Urology 68, Supplement, 2006, 206).

In patients with NMIBC, HAL-guided cystoscopy and TUR has increaseddetection of both papillary tumors and flat carcinoma-in-situ (CIS)lesions, the latter of which are difficult to detect with white lightalone. HAL-guided TUR of bladder cancer in patients with NMIBC hasfurther reduced the rate of residual tumor after such procedures and hasled to superior recurrence free survival (RFS) rates and prolonged RFSintervals compared to white light TUR alone (see Rink et al., Eur Urol4(64), 2013, 624). It is believed that superior RFS rates in patientswho underwent HAL-guided TUR of bladder cancer is due to improveddetection rates and resection of otherwise undetected tumors (Burger etal., Eur Urol 5(64), 2013, 846-854). Existing European guidelines onNMIBC and several expert groups' consensus statements recommend the useof HAL-guided TUR in various settings of management of NMIBC and someeven recommend its use in all NMIBC patients at initial TUR (Witjes etal., Eur Urol 1(66), 2014, 863).

Detection of all tumor lesions during TUR and the rate of residual tumorin the bladder in patients with MIBC is not an issue, the bladder isremoved in its entirety anyway. Hence, TUR in patients with MIBC isusually performed with white light alone and there is no guidelinerecommendation of using HAL-guidance under such TURs. However,HAL-guided TUR seems to have an impact on recurrence free survival alsoin patients who undergo cystectomy: in 268 consecutive patients whounderwent cystectomy for bladder cancer it was retrospectivelyinvestigated whether patients prior to the cystectomy had undergoneHAL-guided TUR or whether TUR was carried out with white light alone.Kaplan-Meier analysis was used to estimate recurrence-free survival(RFS) and overall survival (OS). The 3-year RFS was 69.8% in patientswith HAL-guided TUR and 58.2% in patients with white light TUR alone.The 3-year OS was 65.0% in patients with HAL-guided TUR and 56.6%. Theseresults indicate that HAL-guided TUR is associated with improved RFSafter cystectomy in patients with MIBC (Gakis et al., Urology Vol. 82,Issue 3, Supplement, 2013, Unmoderated Posters, UP.046).

PDT—as PDD—involves the administration of a photosensitizer or aprecursor thereof (i.e. a “photosensitizing agent”) to an area ofinterest. The therapeutic effect of PDT is based on a phototoxicreaction: the photosensitizer or precursor thereof is taken up into thecells, where a precursor of a photosensitizer is converted into anactive photosensitizer. Upon exposure of the area of interest to lightof a suitable wavelength, the photosensitizer is excited from a groundsinglet state to an excited singlet state. It then undergoes intersystemcrossing to a longer-lived excited triplet state. One of the fewchemical species present in tissue with a ground triplet state ismolecular oxygen. When the photosensitizer and an oxygen molecule are inproximity, an energy transfer can take place that allows thephotosensitizer to relax to its ground singlet state, and create anexcited singlet state oxygen molecule. Singlet oxygen is a veryaggressive chemical species and will rapidly react with any nearbybiomolecules. Ultimately, these reactions will kill cells, i.e. cancercells.

PDT has been previously suggested for the treatment of bladder cancerand clinical studies have been carried out to investigate efficacy andsafety of such treatment.

Berger et al., Urol 2003, 61(2), 338-341, have used PDT as first linetreatment in bladder cancer patients. The precursor 5-aminolevulinicacid (5-ALA) was instilled as a solution into the bladder. PDT wascarried out with red light (633 nm) with a laser system and a probepositioned in the center of the bladder to ensure that the entire insideof the bladder receives the same light dose. Light doses of 30 J/cm² and50 J/cm² were provided over a period of 16 to 32 minutes (meanirradiation time 21 minutes). With the aforementioned light doses, themean fluence rate (calculated as light dose divided by time [s]) wasthus 23.8 and 39.7 mW/cm². Side effects in the form of irritatingurinary symptoms occurred in all patients and in 13% of the patients,these symptoms did not resolve before 2 weeks.

Waidelich et al., Urol 2003, 61(2), 332-337 also used 5-ALA but choseirradiation with white light from a xenon bulb. The light wastransmitted into the bladder via a glass fiber which was inserted intothe working channel of a cystoscope. Centration of the tip of the fiberwas done with the help of a balloon catheter which was specificallydesigned for the procedure on the basis of a transurethral irrigationcatheter. The position to the tip of the fiber was monitored byultrasound. PDT was performed under general anesthesia and a light doseof 100 J/cm² was provided over a period of 60 to 150 minutes (i.e. at afluence rate of 11.1-27.7 mW/cm²). From the 12 patients that weretreated, all patients complained about urinary frequency and urgencythat was medically treated. In 7 patients, the symptoms subsided withina week while in 5 patients, they persisted for 3 weeks

Skyrme et al., BJU Int 2005, 95(5), 1206-1210, used PDT as an adjuvantbladder cancer treatment to intravesical chemotherapy with mitomycin.Subsequent to mitomycin treatment, 5-ALA PDT was carried out undergeneral or spinal anesthesia with red laser light irradiation (635 nm)which was transmitted inside the bladder via a diffusor-tipped laserfiber that was inserted into the working channel of a cystoscope.However, centration turned out to be challenging, visualization byultrasound proved to be difficult and treatment needed to be interruptedat 5 minutes intervals to ensure that there was neither decompressionnor contact between the fiber tip and bladder wall. Light doses of 10,15 and 25 J/cm² were provided for this treatment, at a fluence rate of18 mW/cm². A light dose of 25 J/cm² was considered the upper limit oftolerability for this therapy in terms of side effects.

Also HAL has been used in PDT of bladder cancer. Bader et al., Urol.Oncol. Seminars and Original Investigations 31, 2013, 1178-1183, haveused solutions of HAL (8 mM and 16 mM) and irradiation was carried outwith white light from a xenon bulb, transmitted into the bladder via aglass fiber, which was inserted into the working channel of acystoscope. Patients received 3 HAL PDTs each six weeks apart, whichwere performed under general anesthesia. A light dose of 100 J/cm² wasprovided, but a subset of patients received 25 J/cm² at the firsttreatment, 50 J/cm² at the second treatment and 100 J/cm² at the thirdtreatment. Those patients also had local anesthesia instead of generalanesthesia. Irradiation was carried out over a period of 52-100 minutes,i.e. the fluence rate range calculated based on light dose andirradiation time was from 4 mW/cm² (25 J/cm² for 100 min) to 32 mW/cm²(100 J/cm² for 52 min). Standard HAL TUR was carried out prior to eachPDT procedure and any papillary tumor seen at this point was resectedprior to the PDT. After PDT, the bladder was again inspected with bluelight. 128 adverse effects were reported in 17 patients (about 88%) and7 severe adverse effects were reported in 4 patients (23.5%), 2 of whichwere considered to relate to the PDT. Of the 17 patients included, 9were tumor-free at 6 months (52.9%), 4 were tumor-free at 9 months(23.5%) and 2 were tumor-free at 21 months (11.8%).

The disadvantage of the methods described above is that speciallydesigned equipment is needed to carry out PDT, which is not commerciallyavailable. Furthermore, the use of light fibers and placement of the tipof said light fibers in the center of the bladder is complicated andcumbersome, the location of the fiber tip needs to be verified byultrasound or the PDT procedure needs to be interrupted to make surethat the fiber tip is still in the center and does not touch the bladderwall, which could lead to injuries. Further, side-effects are frequentand, depending on the PDT parameters used, may take a long time beforethey are resolved.

Hence there is a need for novel and improved methods of photodynamictherapy for bladder cancer.

In a first embodiment the invention provides a method of photodynamictherapy for bladder cancer, comprising the instillation into the bladderof a patient in need of such treatment of a composition comprising hexyl5-ALA ester (HAL) or a pharmaceutically acceptable salt thereof andexposing the inside of said bladder to blue light having a fluence rateof 1.5 to 12.5 mW/cm². In a first preferred embodiment, the inventionprovides a method of photodynamic therapy for bladder cancer, comprisingthe instillation into the bladder of a patient in need of such treatmentof a composition comprising hexyl 5-ALA ester (HAL) or apharmaceutically acceptable salt thereof, and exposing the inside ofsaid bladder to blue light having a fluence rate of 1.5 to 12.5 mW/cm²,wherein said blue light is provided at light dose of 0.2 to 15 J/cm².

In an alternative first embodiment, the invention provides a compositioncomprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable saltthereof for use in a method of photodynamic therapy for bladder cancer,wherein said composition is instilled into the bladder of a patient inneed of such treatment, and the inside of said bladder is exposed toblue light having a fluence rate of 1.5 to 12.5 mW/cm². In a preferredalternative first embodiment, the invention provides a compositioncomprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable saltthereof for use in a method of photodynamic therapy for bladder cancer,wherein said composition is instilled into the bladder of a patient inneed of such treatment, and the inside of said bladder is exposed toblue light having a fluence rate of 1.5 to 12.5 mW/cm2, wherein saidblue light is provided at light dose of 0.2 to 15 J/cm².

Without wanting to be bound to this theory, the photodynamic therapyaccording to the invention seems to impact bladder cancer on differentlevels: if the method of the invention is carried out together with aTUR, due to a phototoxic reaction as described above, residual tumorcells, i.e. tumor cells which have not been removed during TUR and/orre-attached tumor cells, i.e. tumor cells which have been detachedduring the TUR but which remain in the bladder due to insufficientflushing, are killed. On the other hand, the photodynamic therapyaccording to the invention seems to stimulate the patient's immunesystem to fight the bladder cancer, see Example 3 in this application.The photodynamic therapy according to the invention can be carried outwith commercially available equipment, see below, and is very welltolerated, with only few and transient adverse events (see Fradet etal., J. Urol. 2007, 178, 68-73).

The bladder cancer in the context of the invention is either muscularinvasive bladder cancer (MIBC) or non-muscular invasive bladder cancer(NMIBC). In the context of the first embodiment above, the bladdercancer is preferably NMIBC, which appears as papillary tumors and flatlesions (carcinoma in situ, CIS).

The term “hexyl 5-ALA ester” (HAL) denotes n-hexyl aminolevulinate, i.e.n-hexyl 5-amino-4-oxo-pentanoate.

The term “pharmaceutically acceptable salt” denotes a salt that issuitable for and fulfils the requirements related to for instancesafety, bioavailability and tolerability (see for instance P. H. Stahlet al. (eds.) Handbook of Pharmaceutical Salts, Publisher HelveticaChimica Acta, Zurich, 2002).

The synthesis of hexyl 5-ALA ester is known in the art. It may e.g. beprepared as described in WO 96/28412, the entire contents of which areincorporated herein by reference. Briefly, hexyl 5-ALA ester may beprepared by reaction of 5-ALA with hexanol in the presence of acatalyst, e.g. an acid. Further, hexyl 5-ALA ester hydrochloride iscommercially available, e.g. in the form of Hexvix® (e.g. Photocure ASA)or Cysview® (e.g. Photocure Inc.).

The hexyl 5-ALA ester for use in the invention is preferably in the formof a pharmaceutically acceptable salt. Such salts are preferably acidaddition salts with pharmaceutically acceptable organic or inorganicacids. Suitable acids include, for example, hydrochloric, nitric,hydrobromic, phosphoric, sulfuric, sulfonic acid and sulfonic acidderivatives, the salts of ALA-esters and the latter acids are describedin WO 2005/092838, the entire contents of which are incorporated hereinby reference. A preferred acid is hydrochloride acid, HCl. Syntheticprocedures for salt formation are conventional in the art and are forinstance described in WO 2005/092838.

The concentration of HAL in the composition for use in the invention isconveniently in the range of 0.1 to 5% by weight of the total weight ofthe composition or the equivalent concentration of a pharmaceuticallyacceptable salt of HAL, preferably 0.15 to 3.5%, and most preferably0.17%, which corresponds to e.g. 0.2% HAL hydrochloride (8 mM).

The composition for use in the invention may comprise pharmaceuticallyacceptable carriers, excipients, or stabilizers. The composition for usein the invention is preferably a liquid composition, more preferably asuspension or even more preferably a solution of HAL in a liquidcarrier. Preferred liquid carriers are water or aqueous solutions, mostpreferred liquid carriers are aqueous buffers.

In a preferred embodiment, the composition for use in the invention isan aqueous solution of HAL and most preferably a solution of HAL in anaqueous buffer, preferably a phosphate buffer. In a particularlypreferred embodiment, the composition for use in the invention comprisesas a liquid carrier an aqueous phosphate buffer comprising disodiumphosphate dehydrate, potassium dihydrogen phosphate, sodium chloride,hydrochloric acid, sodium hydroxide and water.

In a preferred embodiment, HAL or the pharmaceutically acceptable saltthereof is provided in a lyophilized form, and is reconstituted in aliquid carrier, preferably in water or an aqueous solution, mostpreferably in an aqueous buffer, prior to use.

If the composition for use in the invention is a liquid compositioncomprising water, the pH of said composition is preferably in the rangeof 4.5 to 7.5, more preferably a pH in the range of 5.7 to 7.2.

In a particularly preferred embodiment, the composition for use of theinvention is Hexvix®, i.e. a solution of HAL hydrochloride (2 mg/ml; 8mM) in an aqueous buffer comprising disodium phosphate dehydrate,potassium dihydrogen phosphate, sodium chloride, hydrochloric acid,sodium hydroxide and water.

The amount of the composition, which is instilled into the bladder, mayvary according to the bladder volume and size. In general, and asobserved in the use of Hexvix®, a volume of about 50 ml of thecomposition comprising 0.2% HAL hydrochloride (8 mM) is suitable andsufficient.

The composition for use in the invention is instilled preferably intothe empty bladder through a catheter and is left in the bladder fromabout 20 minutes to about 3 hours, more preferably from about 30 minutesto about 2 hours, most preferably no less than about 1 hour. Prior toexposing the inside of the bladder to light, the bladder is evacuated.If the patient cannot retain the composition for about 1 hour, at leastabout 1 hour should be allowed to pass from the instillation of thecomposition into the bladder to the start of exposing the inside of thebladder to light.

In a preferred embodiment, Hexvix® is instilled into the bladder througha catheter and is left in the bladder for about 1 hour. The bladder isthen evacuated, before the inside of the bladder is exposed to light. Ifthe patient cannot retain the composition for about 1 hour, at leastabout 1 hour is allowed to pass from the instillation of Hexvix® to thestart of exposing the inside of the bladder to light.

In the method of the invention, the inside of the bladder is exposed toblue light having a fluence rate of 1.5 to 12.5 mW/cm². In a preferredembodiment, the inside of the bladder is exposed to blue light having afluence rate of 2.5 to 7.0 mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm² or 5.5 to8.5 mW/cm², e.g. 6.0, 6.5. 7.0, 7.5 or 8.0 mW/cm².

In a preferred method of the invention, the inside of the bladder isexposed to blue light having a fluence rate of 1.5 to 12.5 mW/cm² andsaid blue light is provided at a light dose of 0.2 to 15 J/cm². In amore preferred embodiment, the inside of the bladder is exposed to bluelight having a fluence rate of 1.5 to 12.5 mW/cm² and blue light isprovided at a light dose of 0.3 to 8.0 J/cm², e.g. 6.5, 7.0 or 7.5J/cm².

In yet another preferred embodiment, the inside of the bladder isexposed to blue light having a fluence rate of 2.5 to 7.0 mW/cm², e.g.5.5, 6.0 or 6.5 mW/cm² or to blue light having a fluence rate of 5.5 to8.5 mW/cm², e.g. 6.0, 6.5. 7.0, 7.5 or 8.0 mW/cm² and said blue light isprovided at a light dose of 0.2 to 15 J/cm². In a more preferredembodiment, the inside of the bladder is exposed to blue light having afluence rate of 2.5 to 7.0 mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm² or toblue light having a fluence rate of 5.5 to 8.5 mW/cm², e.g. 6.0, 6.5.7.0, 7.5 or 8.0 mW/cm² and said blue light is provided at a light doseof 0.7 to 10.2 J/cm². In another more preferred embodiment, the insideof the bladder is exposed to blue light having a fluence rate of 2.5 to7.0 mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm² or to blue light having afluence rate of 5.5 to 8.5 mW/cm², e.g. 6.0, 6.5. 7.0, 7.5 or 8.0 mW/cm²and said blue light is provided at a light dose of 0.3 to 8.0 J/cm²,e.g. 6.5, 7.0 or 7.5 J/cm².

In yet another preferred embodiment, the inside of the bladder isexposed to blue light having a fluence rate of 2.5 to 7.0 mW/cm², e.g.5.5, 6.0 or 6.5 mW/cm² and said blue light is provided at a light doseof 0.3 to 8.0 J/cm², e.g. 6.5, 7.0 or 7.5 J/cm². In yet anotherpreferred embodiment, the inside of the bladder is exposed to blue lighthaving a fluence rate of 5.5 to 8.5 mW/cm², e.g. 6.0, 6.5. 7.0, 7.5 or8.0 mW/cm² and said blue light is provided at a light dose of 0.7 to10.2.0 J/cm².

In another embodiment, the invention provides a method of photodynamictherapy for bladder cancer, comprising the instillation into the bladderof a patient in need of such treatment of a composition comprising hexyl5-ALA ester (HAL) or a pharmaceutically acceptable salt thereof,exposing the inside of said bladder to white light having a fluence rateof 3.0 to 22.0 mW/cm² and to blue light having a fluence rate of 1.5 to12.5 mW/cm². In a preferred embodiment, the invention provides a methodof photodynamic therapy for bladder cancer, comprising the instillationinto the bladder of a patient in need of such treatment of a compositioncomprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable saltthereof, exposing the inside of said bladder to white light having afluence rate of 3.0 to 22.0 mW/cm² and to blue light having a fluencerate of 1.5 to 12.5 mW/cm², wherein said white light is provided at alight dose of 0.4 to 26.5 J/cm² and said blue light at light dose of 0.2to 15 J/cm².

In an alternative embodiment, the invention provides a compositioncomprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable saltthereof for use in a method of photodynamic therapy for bladder cancer,wherein said composition is instilled into the bladder of a patient inneed of such treatment and the inside of said bladder is exposed towhite light having a fluence rate of 3.0 to 22.0 mW/cm² and to bluelight having a fluence rate of 1.5 to 12.5 mW/cm². In a preferredalternative embodiment, the invention provides a composition comprisinghexyl 5-ALA ester (HAL) or a pharmaceutically acceptable salt thereoffor use in a method of photodynamic therapy for bladder cancer, whereinsaid composition is instilled into the bladder of a patient in need ofsuch treatment and the inside of said bladder is exposed to white lighthaving a fluence rate of 3.0 to 22.0 mW/cm² and to blue light having afluence rate of 1.5 to 12.5 mW/cm² and wherein said white light isprovided at a light dose of 0.4 to 26.5 J/cm2 and said blue light isprovided at light dose of 0.2 to 15 J/cm².

In a preferred embodiment, the inside of the bladder is exposed to whitelight having a fluence rate of 5.0 to 12.5 mW/cm², e.g. 7.0, 9.0 or 11.0mW/cm², and to blue light having a fluence rate of 2.5 to 7.0 mW/cm²,e.g. 5.5, 6.0 or 6.5 mW/cm².

In a further preferred embodiment, the inside of the bladder is exposedto white light having a fluence rate of 5.0 to 12.5 mW/cm², e.g. 7.0,9.0 or 11.0 mW/cm², and to blue light having a fluence rate of 2.5 to7.0 mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm², wherein said blue light isprovided at light dose of 0.3 to 8.0 J/cm², e.g. 6.5, 7.0 or 7.5 J/cm²and said white light at a light dose of 0.6 to 15.0 J/cm², e.g. 10.0,11.5 or 13.0 J/cm².

Generally, irradiation, i.e. exposure of the inside of the bladder toblue or white and blue light, is carried out for a period of 2 to 20minutes.

For exposing the inside of the bladder to light, blue light, i.e.wavelengths of from about 360 nm to about 450 nm, is used. In anotherembodiment, white light, i.e. visible light with wavelengths of fromabout 350 to about 700 nm and blue light, i.e. wavelengths of from about360 nm to about 450 nm, is used. For both blue light and white lightexposure, the inside of the bladder may first be exposed to white lightand then to blue light or vice versa. In a preferred embodiment, theinside of the bladder is first exposed to white light, then to bluelight.

The light source may be a lamp or laser. In a preferred embodiment, acommercially available, rigid or flexible blue-light cystoscope (e.g.from Karl Storz, Olympus, Richard Wolf) is used in the method ofphotodynamic therapy of the invention as the light source. Suchblue-light cystoscopes allow for both white and blue light irradiation,and no modifications such as light fibers or diffusing tips are neededto use such cystoscopes in the method of the invention. Commerciallyavailable cystoscopes are equipped with a lamp, e.g. a xenon arc lampwhich emits white light and means to provide blue light, e.g. a filtersystem blocks all other wavelengths than those of blue light.

In a second embodiment, the invention provides a method of photodynamictherapy for bladder cancer, comprising the instillation into the bladderof a patient of a solution of HAL hydrochloride in an aqueous buffer,and exposing the inside of said bladder to blue light having a fluencerate of 1.5 to 12.5 mW/cm². In a preferred second embodiment, said bluelight is provided at a light dose of 0.2 to 15.0 J/cm². In anotherpreferred second embodiment, the inside of said bladder is exposed towhite light having a fluence rate of 3.0 to 22.0 mW/cm² and to bluelight having a fluence rate of 1.5 to 12.5 mW/cm². In yet anotherpreferred second embodiment, the inside of said bladder is exposed towhite light having a fluence rate of 3.0 to 22.0 mW/cm² and to bluelight having a fluence rate of 1.5 to 12.5 mW/cm², wherein said whitelight is provided at a light dose of 0.4 to 26.5 J/cm² and said bluelight at light dose of 0.2 to 15.0 J/cm².

In the second embodiment and in all the preferred second embodiments,the solution comprises 2 mg/ml HAL hydrochloride. Preferred fluencerates and/or light doses for blue light have been disclosed before andare preferably used in this second embodiment. Further, preferredfluence rates and/or light doses for white light have been disclosedbefore and are preferably used in this second embodiment. Also,preferred combinations of fluence rates and/or light doses for bluelight and of fluence rates and/or light doses for white have beendisclosed before and are preferably used in this second embodiment.

In a third embodiment, the invention provides a method of photodynamictherapy for bladder cancer, comprising the instillation into the bladderof a patient of a solution of HAL hydrochloride in an aqueous buffer,and exposing the inside of said bladder to blue light having a fluencerate of 2.5 to 7.0 mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm² or 5.5 to 8.5mW/cm², e.g. 6.0, 6.5. 7.0, 7.5 or 8.0 mW/cm². In a preferred thirdembodiment, said blue light is provided at a light dose of 0.7 to 10.2J/cm² or 0.3 to 8.0 J/cm², e.g. 6.5, 7.0 or 7.5 J/cm². In anotherpreferred third embodiment, the inside of said bladder is exposed towhite light having a fluence rate of 5.0 to 12.5 mW/cm², e.g. 7.0, 9.0or 11.0 mW/cm² and to blue light having a fluence rate of 2.5 to 7.0mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm². In yet another preferred thirdembodiment, the inside of said bladder is exposed to white light havinga fluence rate of 5.0 to 12.5 mW/cm², e.g. 7.0, 9.0 or 11.0 mW/cm² andto blue light having a fluence rate of 2.5 to 7.0 mW/cm², e.g. 5.5, 6.0or 6.5 mW/cm², wherein said white light is provided at a light dose of0.6 to 15.0 J/cm², e.g. 10.0, 11.5 or 13.5 J/cm² and said blue light atlight dose of 0.3 to 8.0 J/cm² e.g. 6.5, 7.0 or 7.5 J/cm².

In the third embodiment and in all the preferred third embodiments, thesolution comprises 2 mg/ml HAL hydrochloride. Preferred fluence ratesand/or light doses for blue light have been disclosed before and arepreferably used in this third embodiment. Further, preferred fluencerates and/or light doses for white light have been disclosed before andare preferably used in this third embodiment. Also, preferredcombinations of fluence rates and/or light doses for blue light and offluence rates and/or light doses for white have been disclosed beforeand are preferably used in this third embodiment.

In a fourth embodiment, the invention provides a method of photodynamictherapy for bladder cancer, comprising the instillation into the bladderof a patient of a solution of HAL hydrochloride in an aqueous buffercomprising disodium phosphate dehydrate, potassium dihydrogen phosphate,sodium chloride, hydrochloric acid, sodium hydroxide and water, andexposing the inside of said bladder to blue light having a fluence rateof 1.5 to 12.5 mW/cm². In a preferred fourth embodiment, said blue lightis provided at a light dose of 0.2 to 15.0 J/cm². In another preferredfourth embodiment, the inside of said bladder is exposed to white lighthaving a fluence rate of 3.0 to 22.0 mW/cm² and to blue light having afluence rate of 1.5 to 12.5 mW/cm². In yet another preferred fourthembodiment, the inside of said bladder is exposed to white light havinga fluence rate of 3.0 to 22.0 mW/cm² and to blue light having a fluencerate of 1.5 to 12.5 mW/cm², wherein said white light is provided at alight dose of 0.4 to 26.5 J/cm² and said blue light at light dose of 0.2to 15.0 J/cm².

In the fourth embodiment and in all the preferred fourth embodiments,the solution comprises 2 mg/ml HAL hydrochloride. Preferred fluencerates and/or light doses for blue light have been disclosed before andare preferably used in this fourth embodiment. Further, preferredfluence rates and/or light doses for white light have been disclosedbefore and are preferably used in this fourth embodiment. Also,preferred combinations of fluence rates and/or light doses for bluelight and of fluence rates and/or light doses for white have beendisclosed before and are preferably used in this fourth embodiment.

In a fifth embodiment, the invention provides a method of photodynamictherapy for bladder cancer, comprising the instillation into the bladderof a patient of a solution of HAL hydrochloride in an aqueous buffercomprising disodium phosphate dehydrate, potassium dihydrogen phosphate,sodium chloride, hydrochloric acid, sodium hydroxide and water, andexposing the inside of said bladder to blue light having a fluence rateof 2.5 to 7.0 mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm² or 5.5 to 8.5 mW/cm²,e.g. 6.0, 6.5. 7.0, 7.5 or 8.0 mW/cm². In a preferred fifth embodiment,said blue light is provided at a light dose of 0.7 to 10.2 J/cm² or 0.3to 8.0 J/cm², e.g. 6.5, 7.0 or 7.5 J/cm². In another preferred fifthembodiment, the inside of said bladder is exposed to white light havinga fluence rate of 5.0 to 12.5 mW/cm², e.g. 7.0, 9.0 or 11.0 mW/cm² andto blue light having a fluence rate of 2.5 to 7.0 mW/cm², e.g. 5.5, 6.0or 6.5 mW/cm². In yet another preferred fifth embodiment, the inside ofsaid bladder is exposed to white light having a fluence rate of 5.0 to12.5 mW/cm², e.g. 7.0, 9.0 or 11.0 mW/cm² and to blue light having afluence rate of 2.5 to 7.0 mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm², whereinsaid white light is provided at a light dose of 0.6 to 15.0 J/cm², e.g.10.0, 11.5 or 13.5 J/cm² and said blue light at light dose of 0.3 to 8.0J/cm² e.g. 6.5, 7.0 or 7.5 J/cm².

In the fifth embodiment and in all the preferred fifth embodiments, thesolution comprises 2 mg/ml HAL hydrochloride. Preferred fluence ratesand/or light doses for blue light have been disclosed before and arepreferably used in this fifth embodiment. Further, preferred fluencerates and/or light doses for white light have been disclosed before andare preferably used in this fifth embodiment. Also, preferredcombinations of fluence rates and/or light doses for blue light and offluence rates and/or light doses for white have been disclosed beforeand are preferably used in this fifth embodiment.

In a sixth embodiment, the invention provides a method of photodynamictherapy for bladder cancer, comprising the instillation into the bladderof a patient of a solution of HAL hydrochloride in an aqueous buffer,and exposing the inside of said bladder to blue light having a fluencerate of 1.5 to 12.5 mW/cm², wherein said blue light is provided at alight dose of 0.2 to 15.0 J/cm². In a preferred sixth embodiment, theinside of said bladder is exposed to white light having a fluence rateof 3.0 to 22.0 mW/cm² and to blue light having a fluence rate of 1.5 to12.5 mW/cm², wherein said white light is provided at a light dose of 0.4to 26.5 J/cm² and said blue light at light dose of 0.2 to 15.0 J/cm².

In the sixth embodiment and in the preferred sixth embodiment, thesolution comprises 2 mg/ml HAL hydrochloride. Preferred fluence ratesand/or light doses for blue light have been disclosed before and arepreferably used in this sixth embodiment. Further, preferred fluencerates and/or light doses for white light have been disclosed before andare preferably used in this sixth embodiment. Also, preferredcombinations of fluence rates and/or light doses for blue light and offluence rates and/or light doses for white have been disclosed beforeand are preferably used in this sixth embodiment.

In a seventh embodiment, the invention provides a method of photodynamictherapy for bladder cancer, comprising the instillation into the bladderof a patient of a solution of HAL hydrochloride in an aqueous buffer,and exposing the inside of said bladder to blue light having a fluencerate of 2.5 to 7.0 mW/cm² e.g. 5.5, 6.0 or 6.5 mW/cm² or 5.5 to 8.5mW/cm², e.g. 6.0, 6.5. 7.0, 7.5 or 8.0 mW/cm², wherein said blue lightis provided at a light dose of 0.7 to 10.2 J/cm² or 0.3 to 8.0 J/cm²,e.g. 6.5, 7.0 or 7.5 J/cm². In a preferred seventh embodiment, theinside of said bladder is exposed to white light having a fluence rateof 5.0 to 12.5 mW/cm², e.g. 7.0, 9.0 or 11.0 mW/cm² and to blue lighthaving a fluence rate of 2.5 to 7.0 mW/cm² e.g. 5.5, 6.0 or 6.5 mW/cm²,wherein said white light is provided at a light dose of 0.6 to 15.0J/cm², e.g. 10.0, 11.5 or 13.5 J/cm² and said blue light at light doseof 0.3 to 8.0 J/cm², e.g. 6.5, 7.0 or 7.5 J/cm².

In the seventh embodiment and in the preferred seventh embodiment, thesolution comprises 2 mg/ml HAL hydrochloride. Preferred fluence ratesand/or light doses for blue light have been disclosed before and arepreferably used in this seventh embodiment. Further, preferred fluencerates and/or light doses for white light have been disclosed before andare preferably used in this seventh embodiment. Also, preferredcombinations of fluence rates and/or light doses for blue light and offluence rates and/or light doses for white have been disclosed beforeand are preferably used in this seventh embodiment.

In an eighth embodiment, the invention provides a method of photodynamictherapy for bladder cancer, comprising the instillation into the bladderof a patient of a solution of HAL hydrochloride in an aqueous buffercomprising disodium phosphate dehydrate, potassium dihydrogen phosphate,sodium chloride, hydrochloric acid, sodium hydroxide and water, andexposing the inside of said bladder to blue light having a fluence rateof 1.5 to 12.5 mW/cm², wherein said blue light is provided at a lightdose of 0.2 to 15.0 J/cm². In a preferred eighth embodiment, the insideof said bladder is exposed to white light having a fluence rate of 3.0to 22.0 mW/cm² and to blue light having a fluence rate of 1.5 to 12.5mW/cm², wherein said white light is provided at a light dose of 0.4 to26.5 J/cm² and said blue light at light dose of 0.2 to 15.0 J/cm².

In the eighth embodiment and in the preferred eighth embodiment, thesolution comprises 2 mg/ml HAL hydrochloride. Preferred fluence ratesand/or light doses for blue light have been disclosed before and arepreferably used in this eighth embodiment. Further, preferred fluencerates and/or light doses for white light have been disclosed before andare preferably used in this eighth embodiment. Also, preferredcombinations of fluence rates and/or light doses for blue light and offluence rates and/or light doses for white have been disclosed beforeand are preferably used in this eighth embodiment.

In a ninth embodiment, the invention provides a method of photodynamictherapy for bladder cancer, comprising the instillation into the bladderof a patient of a solution of HAL hydrochloride in an aqueous buffercomprising disodium phosphate dehydrate, potassium dihydrogen phosphate,sodium chloride, hydrochloric acid, sodium hydroxide and water, andexposing the inside of said bladder to blue light having a fluence rateof 2.5 to 7.0 mW/cm² e.g. 5.5, 6.0 or 6.5 mW/cm² or 5.5 to 8.5 mW/cm²,e.g. 6.0, 6.5. 7.0, 7.5 or 8.0 mW/cm², wherein said blue light isprovided at a light dose of 0.7 to 10.2 J/cm² or 0.3 to 8.0 J/cm², e.g.6.5, 7.0 or 7.5 J/cm². In a preferred ninth embodiment, the inside ofsaid bladder is exposed to white light having a fluence rate of 5.0 to12.5 mW/cm², e.g. 7.0, 9.0 or 11.0 mW/cm² and to blue light having afluence rate of 2.5 to 7.0 mW/cm² e.g. 5.5, 6.0 or 6.5 mW/cm², whereinsaid white light is provided at a light dose of 0.6 to 15.0 J/cm², e.g.10.0, 11.5 or 13.5 J/cm² and said blue light at light dose of 0.3 to 8.0J/cm², e.g. 6.5, 7.0 or 7.5 J/cm².

In the ninth embodiment and in the preferred ninth embodiment, thesolution comprises 2 mg/ml HAL hydrochloride. Preferred fluence ratesand/or light doses for blue light have been disclosed before and arepreferably used in this ninth embodiment. Further, preferred fluencerates and/or light doses for white light have been disclosed before andare preferably used in this ninth embodiment. Also, preferredcombinations of fluence rates and/or light doses for blue light and offluence rates and/or light doses for white have been disclosed beforeand are preferably used in this ninth embodiment.

In said second to ninth embodiment, the light source is preferably acommercially available blue-light cystoscope which allows blue lightirradiation or for blue and white light irradiation.

In said second to ninth embodiment, said solution of HAL hydrochlorideis instilled into the bladder through a catheter and is preferably leftin the bladder for about 1 hour. In a preferred second to ninthembodiment, the bladder is evacuated prior to exposing the inside of thebladder to light. If the patient cannot retain the said solution forabout 1 hour, at least about 1 hour is allowed to pass from theinstillation of the solution to the start of exposing the inside of thebladder to light.

The method of photodynamic therapy for bladder cancer according to theinvention can be used as stand-alone bladder cancer treatment.Alternatively, it can be used as adjuvant therapy in the treatment ofbladder cancer, i.e. in addition to a primary/main therapy for bladdercancer.

Hence, in a tenth embodiment, the invention provides a method oftreating bladder cancer wherein a method of photodynamic therapy is usedas adjuvant therapy, said method of photodynamic therapy comprises theinstillation into the bladder of a patient of a composition comprisinghexyl 5-ALA ester (HAL) or a pharmaceutically acceptable salt thereof,and exposing the inside of said bladder to blue light having a fluencerate of 1.5 to 12.5 mW/cm². In a preferred tenth embodiment, said bluelight is provided at a light dose of 0.2 to 15.0 J/cm². In anotherpreferred tenth embodiment, the inside of said bladder is exposed towhite light having a fluence rate of 3.0 to 22.0 mW/cm² and to bluelight having a fluence rate of 1.5 to 12.5 mW/cm². In yet anotherpreferred tenth embodiment, the inside of said bladder is exposed towhite light having a fluence rate of 3.0 to 22.0 mW/cm² and to bluelight having a fluence rate of 1.5 to 12.5 mW/cm², wherein said whitelight is provided at a light dose of 0.4 to 26.5 J/cm² and said bluelight at light dose of 0.2 to 15.0 J/cm².

In an eleventh embodiment, the invention provides a method of treatingbladder cancer wherein a method of photodynamic therapy is used asadjuvant therapy, said method of photodynamic therapy comprises theinstillation into the bladder of a patient of a composition comprisinghexyl 5-ALA ester (HAL) or a pharmaceutically acceptable salt thereof,and exposing the inside of said bladder to blue light having a fluencerate of 2.5 to 7.0 mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm² or 5.5 to 8.5mW/cm², e.g. 6.0, 6.5. 7.0, 7.5 or 8.0 mW/cm². In a preferred eleventhembodiment, said blue light is provided at a light dose of 0.7 to 10.2J/cm² or 0.3 to 8.0 J/cm², e.g. 6.5, 7.0 or 7.5 J/cm². In anotherpreferred eleventh embodiment, the inside of said bladder is exposed towhite light having a fluence rate of 5.0 to 12.5 mW/cm², e.g. 7.0, 9.0or 11.0 mW/cm² and to blue light having a fluence rate of 2.5 to 7.0mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm². In yet another preferred eleventhembodiment, the inside of said bladder is exposed to white light havinga fluence rate of 5.0 to 12.5 mW/cm², e.g. 7.0, 9.0 or 11.0 mW/cm² andto blue light having a fluence rate of 2.5 to 7.0 mW/cm², e.g. 5.5, 6.0or 6.5 mW/cm², wherein said white light is provided at a light dose of0.6 to 15.0 J/cm², e.g. 10.0, 11.5 or 13.5 J/cm² and said blue light atlight dose of 0.3 to 8.0 J/cm² e.g. 6.5, 7.0 or 7.5 J/cm².

In an alternative tenth embodiment, the invention provides a compositioncomprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable saltthereof for use in a method of treating bladder cancer wherein a methodof photodynamic therapy is used as adjuvant therapy, said method ofphotodynamic therapy comprises the instillation of the composition intothe bladder of a patient in need of such treatment and exposing theinside of said bladder to blue light having a fluence rate of 1.5 to12.5 mW/cm². In a preferred alternative tenth embodiment, said bluelight is provided at a light dose of 0.2 to 15.0 J/cm². In anotherpreferred alternative tenth embodiment, the inside of said bladder isexposed to white light having a fluence rate of 3.0 to 22.0 mW/cm² andto blue light having a fluence rate of 1.5 to 12.5 mW/cm². In yetanother preferred alternative tenth embodiment, the inside of saidbladder is exposed to white light having a fluence rate of 3.0 to 22.0mW/cm² and to blue light having a fluence rate of 1.5 to 12.5 mW/cm²,wherein said white light is provided at a light dose of 0.4 to 26.5J/cm² and said blue light at light dose of 0.2 to 15.0 J/cm².

In an alternative eleventh embodiment, the invention provides acomposition comprising hexyl 5-ALA ester (HAL) or a pharmaceuticallyacceptable salt thereof for use in a method of treating bladder cancerwherein a method of photodynamic therapy is used as adjuvant therapy,said method of photodynamic therapy comprises the instillation of thecomposition into the bladder of a patient in need of such treatment andexposing the inside of said bladder to blue light having a fluence rateof 2.5 to 7.0 mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm² or 5.5 to 8.5 mW/cm²,e.g. 6.0, 6.5. 7.0, 7.5 or 8.0 mW/cm². In a preferred alternativeeleventh embodiment, said blue light is provided at a light dose of 0.7to 10.2 J/cm² or 0.3 to 8.0 J/cm², e.g. 6.5, 7.0 or 7.5 J/cm². Inanother preferred alternative eleventh embodiment, the inside of saidbladder is exposed to white light having a fluence rate of 5.0 to 12.5mW/cm², e.g. 7.0, 9.0 or 11.0 mW/cm² and to blue light having a fluencerate of 2.5 to 7.0 mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm². In yet anotherpreferred alternative eleventh embodiment, the inside of said bladder isexposed to white light having a fluence rate of 5.0 to 12.5 mW/cm², e.g.7.0, 9.0 or 11.0 mW/cm² and to blue light having a fluence rate of 2.5to 7.0 mW/cm², e.g. 5.5, 6.0 or 6.5 mW/cm², wherein said white light isprovided at a light dose of 0.6 to 15.0 J/cm², e.g. 10.0, 11.5 or 13.5J/cm² and said blue light at light dose of 0.3 to 8.0 J/cm² e.g. 6.5,7.0 or 7.5 J/cm².

In a preferred tenth or eleventh embodiment, or in a preferredalternative tenth or eleventh embodiment, the composition for use in themethod is an aqueous solution of HAL and most preferably a solution ofHAL in an aqueous buffer, preferably a phosphate buffer. In aparticularly preferred embodiment, the composition for use in the methodcomprises as a liquid carrier an aqueous phosphate buffer comprisingdisodium phosphate dehydrate, potassium dihydrogen phosphate, sodiumchloride, hydrochloric acid, sodium hydroxide and water.

The bladder cancer in said tenth or eleventh embodiment, or in saidpreferred alternative tenth or eleventh embodiment may be NMIBC or MIBC.

Usually, for NMIBC, the main treatment is TUR, i.e. a procedure wherethe bladder is visualized through the urethra and tumors and lesions areresected. TUR is often followed by immune- and/or chemotherapy.

The method of photodynamic therapy of the invention is preferablycarried out as adjuvant therapy to TUR in patients who are in need ofsuch treatment, i.e. patients who have been diagnosed with NMIBC or inpatients who are suspected to have NMIBC.

The adjuvant therapy of the invention may be carried out simultaneouslywith the TUR or after a TUR.

When carried out simultaneously, a method of treating NMIBC thus maycommence with the instillation into the bladder of a patient in need ofsuch treatment of a composition comprising hexyl 5-ALA ester (HAL) or apharmaceutically acceptable salt thereof, and exposing the inside ofsaid bladder to white light for a visual inspection and then switchingto blue light for fluorescence detection and treatment of lesions. Saidlesions are then resected, e.g. under white light. The completeness ofthe resection may be monitored by use of blue light. In the said method,the inside of the bladder is exposed to blue light having a fluence rateof 1.5 to 12.5 mW/cm². In a preferred embodiment, said aforementionedwhite light has a fluence rate of 3.0 to 22.0 mW/cm². In a preferredembodiment, said aforementioned blue light is provided at a light doseof 0.2 to 15.0 J/cm². In a further preferred embodiment, saidaforementioned white light is provided at a light dose of 0.4 to 26.5J/cm². The irradiation/the light exposure is carried out for a period of2 (for small and/or few lesions) to 20 minutes (for large and/ormultiple lesions).

Thus, in an twelfth embodiment, the invention provides a method oftreating NMIBC by simultaneously carrying out an adjuvant therapy and atransurethral resection of NMIBC, said method comprises a) instillationof a composition comprising hexyl 5-ALA ester (HAL) or apharmaceutically acceptable salt thereof into the bladder of a patientin need of such NMIBC treatment, b) exposing the inside of said bladderto white light for a visual inspection followed by exposing said insideto blue light for fluorescence detection and treatment of lesions; c)resection of said lesions; and d) optionally monitoring the completenessof the resection by exposing said inside to blue light for fluorescencedetection of residual NMIBC, wherein the blue light has a fluence rateof 1.5 to 12.5 mW/cm².

In a preferred twelfth embodiment, said blue light is provided at alight dose of 0.2 to 15.0 J/cm². Preferably, the irradiation/the lightexposure is carried out for a period of 2 (for small and/or few lesions)to 20 minutes (for large and/or multiple lesions).

In a further preferred twelfth embodiment, the invention provides amethod of treating NMIBC by simultaneously carrying out an adjuvanttherapy and a transurethral resection of NMIBC, said method comprises a)instillation of a composition comprising hexyl 5-ALA ester (HAL) or apharmaceutically acceptable salt thereof into the bladder of a patientin need of such NMIBC treatment, b) exposing the inside of said bladderto white light for a visual inspection followed by exposing said insideto blue light for fluorescence detection and treatment of lesions; c)resection of said lesions; and d) optionally monitoring the completenessof the resection by exposing said inside to blue light for fluorescencedetection of residual NMIBC, wherein the white light has a fluence rateof 3.0 to 22.0 mW/cm² and the blue light has a fluence rate of 1.5 to12.5 mW/cm².

In yet a further preferred twelfth embodiment, said white light isprovided at a light dose of 0.4 to 26.5 J/cm² and said blue light isprovided at a light dose of 0.2 to 15.0 J/cm². Preferably, theirradiation/the light exposure is carried out for a period of 2 (forsmall and/or few lesions) to 20 minutes (for large and/or multiplelesions).

Various embodiments and preferred embodiments of the method of treatingNMIBC, i.e. embodiments 1-11, are described above and can be used inthis twelfth embodiment.

In an alternative twelfth embodiment, the invention provides acomposition comprising hexyl 5-ALA ester (HAL) or a pharmaceuticallyacceptable salt thereof for use in a method of treating NMIBC bysimultaneously carrying out an adjuvant therapy and a transurethralresection of NMIBC, wherein a) said composition is instilled into thebladder of a patient in need of such NMIBC treatment, b) the inside ofsaid bladder is exposed to white light for a visual inspection followedby exposing said inside to blue light for fluorescence detection andtreatment of lesions; c) said lesions are resected; and d) optionallythe completeness of the resection is monitored by exposing said insideto blue light for fluorescence detection of residual NMIBC, wherein theblue light has a fluence rate of 1.5 to 12.5 mW/cm².

In a preferred alternative twelfth embodiment, said blue light isprovided at a light dose of 0.2 to 15.0 J/cm². Preferably, theirradiation/the light exposure is carried out for a period of 2 (forsmall and/or few lesions) to 20 minutes (for large and/or multiplelesions).

In a further preferred alternative twelfth embodiment, the inventionprovides a composition comprising hexyl 5-ALA ester (HAL) or apharmaceutically acceptable salt thereof for use in a method of treatingNMIBC a method of treating NMIBC by simultaneously carrying out anadjuvant therapy and a transurethral resection of NMIBC, wherein a) saidcomposition is instilled into the bladder of a patient in need of suchNMIBC treatment, b) the inside of said bladder is exposed to white lightfor a visual inspection followed by exposing said inside to blue lightfor fluorescence detection and treatment of lesions; c) said lesions areresected; and d) optionally the completeness of the resection ismonitored by exposing said inside to blue light for fluorescencedetection of residual NMIBC, wherein the white light has a fluence rateof 3.0 to 22.0 mW/cm² and the blue light has a fluence rate of 1.5 to12.5 mW/cm².

In yet a further preferred twelfth embodiment, said white light isprovided at a light dose of 0.4 to 26.5 J/cm² and said blue light isprovided at a light dose of 0.2 to 15.0 J/cm². Preferably, theirradiation/the light exposure is carried out for a period of 2 (forsmall and/or few lesions) to 20 minutes (for large and/or multiplelesions).

Various embodiments and preferred embodiments of the compositioncomprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable saltthereof for use in a method of treating NMIBC, i.e. embodiments 1-11,are described above and can be used in this alternative twelfthembodiment.

When carried out after a TUR, the adjuvant therapy for treating NMIBCmay commence with the instillation into the bladder of a patient havingundergone TUR of a composition comprising hexyl 5-ALA ester (HAL) or apharmaceutically acceptable salt thereof and exposing the inside of saidbladder to blue light having a fluence rate of 1.5 to 12.5 mW/cm².

Thus, in a thirteenth embodiment, the invention provides an adjuvanttherapy for treating NMIBC, comprising instillation of a compositioncomprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable saltthereof into the bladder of a patient having undergone TUR and exposingthe inside of said bladder to blue light having a fluence rate of 1.5 to12.5 mW/cm².

In a preferred thirteenth embodiment, said blue light is provided at alight dose of 0.2 to 15.0 J/cm². Preferably, the irradiation/the lightexposure is carried out for a period of 2 (for small and/or few lesions)to 20 minutes (for large and/or multiple lesions).

In a further preferred thirteenth embodiment, the invention provides anadjuvant therapy for treating NMIBC, comprising instillation of acomposition comprising hexyl 5-ALA ester (HAL) or a pharmaceuticallyacceptable salt thereof into the bladder of a patient having undergoneTUR and exposing the inside of said bladder to white light having afluence rate of 3.0 to 22.0 mW/cm² and to blue light having a fluencerate of 1.5 to 12.5 mW/cm².

In yet a further preferred thirteenth embodiment, said white light isprovided at a light dose of 0.4 to 26.5 J/cm² and said blue light isprovided at a light dose of 0.2 to 15.0 J/cm². Preferably, theirradiation/the light exposure is carried out for a period of 2 (forsmall and/or few lesions) to 20 minutes (for large and/or multiplelesions).

Various embodiments and preferred embodiments of the method of treatingNMIBC, i.e. embodiments 1-11, are described above and can be used inthis thirteenth embodiment.

In an alternative thirteenth embodiment, the invention provides acomposition comprising hexyl 5-ALA ester (HAL) or a pharmaceuticallyacceptable salt thereof for use in an adjuvant therapy for treatingNMIBC, wherein said composition is instilled into the bladder of apatient who has undergone TUR and the inside of said bladder is exposedto blue light having a fluence rate of 1.5 to 12.5 mW/cm².

In a preferred alternative thirteenth embodiment, said blue light isprovided at a light dose of 0.2 to 15.0 J/cm². Preferably, theirradiation/the light exposure is carried out for a period of 2 (forsmall and/or few lesions) to 20 minutes (for large and/or multiplelesions).

In a further preferred alternative thirteenth embodiment, the inventionprovides a composition comprising hexyl 5-ALA ester (HAL) or apharmaceutically acceptable salt thereof for use in an adjuvant therapyfor treating NMIBC, wherein said composition is instilled into thebladder of a patient having undergone TUR and the inside of said bladderis exposed to white light having a fluence rate of 3.0 to 22.0 mW/cm²and to blue light having a fluence rate of 1.5 to 12.5 mW/cm².

In yet a further preferred alternative thirteenth embodiment, said whitelight is provided at a light dose of 0.4 to 26.5 J/cm² and said bluelight is provided at a light dose of 0.2 to 15.0 J/cm². Preferably, theirradiation/the light exposure is carried out for a period of 2 (forsmall and/or few lesions) to 20 minutes (for large and/or multiplelesions).

Various embodiments and preferred embodiments of the compositioncomprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable saltthereof for use in this adjuvant therapy for NMIBC, i.e. embodiments1-11, are described above and can be used in this alternative thirteenthembodiment.

The method of treating NMIBC according to the invention may be carriedout once or repeatedly, e.g. two or more times, e.g. 3, 4, 5 or 6 times,with a period between the treatments of e.g. 4 days to 4 weeks, e.g. 1,2 or 3 weeks.

The adjuvant therapy for NMIBC according to the invention may be carriedout once or repeatedly, e.g. two or more times, e.g. 3, 4, 5 or 6 times,with a period between the treatments of e.g. 4 days to 4 weeks, e.g. 1,2 or 3 weeks, either together with a TUR, e.g. after a TUR, or alone.

The adjuvant therapy for treating NMIBC of the invention can be used incombination with chemotherapy, e.g. systemic or intravesicaladministration of suitable chemotherapeutic agents for NMIBC, such ascisplatin, methotrexate, vinblastine, valrubicin, adriamycin ormitomycin C and/or in combination with suitable immunotherapeutic agentsfor NMIBC, such as systemic administration of anticancer vaccines orintravesical administration of Bacillus Calmette-Guérin (BCG).

Alternatively, the adjuvant therapy for treating NMIBC according to theinvention may replace or partially replace other adjuvant therapies likechemotherapy and/or immunotherapy. In a preferred embodiment, theadjuvant therapy according to the invention replaces or partiallyreplaces other adjuvant therapies which are intravesically administered,e.g. mitomycin and/or BCG. In a particularly preferred embodiment, theadjuvant therapy for treating NMIBC according to the invention partiallyor fully replaces BCG. BCG treatment is usually started a few weeksafter a transurethral resection of NMIBC and is given once a week for 6weeks. The adjuvant therapy according to the invention may replace 1, 2,3, 4, 5 or all 6 of such BCG treatments.

Up to 40% of patients with NMIBC will fail intravesical BCG therapy. Thevast majority of low-grade NMIBC are prone to recur but very rarelyprogress. Failure after intravesical BCG in these patients is usuallysuperficial and low-grade, and such patients can be managed withintravesical regimens, including repeated BCG, BCG plus cytokines,intravesical chemotherapy, thermochemotherapy or new immunotherapeuticmodalities. At the other end of the spectrum, failure to respond to BCGin high-risk T1 bladder cancer and/or carcinoma in situ is moreproblematic, since those tumors often have the potential to progress tomuscle invasion. In these cases, radical cystectomy remains the mainstayafter BCG failure. Hence there is a need to find new therapeuticalternatives for BCG refractory bladder cancer patients and the adjuvanttherapy for treating NMIBC according to the invention meets this need.

Full replacement of BCG by the adjuvant therapy according to theinvention is preferably used in BCG refractory NMIBC patients, i.e.patients where BCG therapy does not lead to the desired treatmentsuccess.

Hence, in a fourteenth embodiment the invention provides a adjuvanttherapy for treating NMIBC in BCG refractory patients, comprisinginstillation of a composition comprising hexyl 5-ALA ester (HAL) or apharmaceutically acceptable salt thereof into the bladder of a BCGrefractory patient and exposing the inside of said bladder to blue lighthaving a fluence rate of 1.5 to 12.5 mW/cm².

In a preferred fourteenth embodiment, said blue light is provided at alight dose of 0.2 to 15.0 J/cm². Preferably, the irradiation/the lightexposure is carried out for a period of 2 (for small and/or few lesions)to 20 minutes (for large and/or multiple lesions).

In a further preferred fourteenth embodiment, the invention provides anadjuvant therapy for treating NMIBC in BCG refractory patients,comprising instillation of a composition comprising hexyl 5-ALA ester(HAL) or a pharmaceutically acceptable salt thereof into the bladder ofa BCG refractory patient and exposing the inside of said bladder towhite light having a fluence rate of 3.0 to 22.0 mW/cm² and to bluelight having a fluence rate of 1.5 to 12.5 mW/cm².

In yet a further preferred fourteenth embodiment, said white light isprovided at a light dose of 0.4 to 26.5 J/cm² and said blue light isprovided at a light dose of 0.2 to 15.0 J/cm². Preferably, theirradiation/the light exposure is carried out for a period of 2 (forsmall and/or few lesions) to 20 minutes (for large and/or multiplelesions).

Various embodiments and preferred embodiments of adjuvant therapy fortreating NMIBC in BCG refractory patients, i.e. embodiments 1-11, aredescribed above and can be used in this fourteenth embodiment.

In an alternative fourteenth embodiment, the invention provides acomposition comprising hexyl 5-ALA ester (HAL) or a pharmaceuticallyacceptable salt thereof for use in an adjuvant therapy for treatingNMIBC in BCG refractory patients, wherein said composition is instilledinto the bladder of a BCG refractory patient and the inside of saidbladder is exposed to blue light having a fluence rate of 1.5 to 12.5mW/cm².

In a preferred alternative fourteenth embodiment, said blue light isprovided at a light dose of 0.2 to 15.0 J/cm². Preferably, theirradiation/the light exposure is carried out for a period of 2 (forsmall and/or few lesions) to 20 minutes (for large and/or multiplelesions).

In a further preferred alternative fourteenth embodiment, the inventionprovides a composition comprising hexyl 5-ALA ester (HAL) or apharmaceutically acceptable salt thereof for use in an adjuvant therapyfor treating NMIBC in BCG refractory patients, wherein said compositionis instilled into the bladder of a BCG refractory patient and the insideof said bladder is exposed to white light having a fluence rate of 3.0to 22.0 mW/cm² and to blue light having a fluence rate of 1.5 to 12.5mW/cm².

In yet a further preferred alternative fourteenth embodiment, said whitelight is provided at a light dose of 0.4 to 26.5 J/cm² and said bluelight is provided at a light dose of 0.2 to 15.0 J/cm². Preferably, theirradiation/the light exposure is carried out for a period of 2 (forsmall and/or few lesions) to 20 minutes (for large and/or multiplelesions).

Various embodiments and preferred embodiments of the compositioncomprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable saltthereof for use in this adjuvant therapy for treating NMIBC in BCGrefractory patients, i.e. embodiments 1-11, are described above and canbe used in this preferred alternative fourteenth embodiment.

For patients with MIBC, the main treatment is radical cystectomy, i.e.removal of the bladder and adjacent organs, i.e. prostate and seminalvesicles in men, and uterus and adnexa in women, including thedissection of regional lymph nodes. Cystectomy is also advocated inpatients with NMIBC who are at high risk of progression, i.e. patientshaving multiple recurrent high-grade tumors or high-grade T1 tumors orhigh-grade tumors with concurrent carcinoma-in-situ (CIS). Further,cystectomy is advocated in patients with NMIBC who have received BCGimmunotherapy but where such treatment has failed.

The method of photodynamic therapy of the invention is preferablycarried out as a neoadjuvant therapy to cystectomy, i.e. prior to such acystectomy, in patients who are in need of such treatment, i.e. patientswho have been diagnosed with MIBC.

Thus, in a fifteenth embodiment, the invention provides a method ofneoadjuvant therapy for treating MIBC prior to a cystectomy, said methodcomprising a) instillation into the bladder of a patient in need of saidtreatment of a composition comprising hexyl 5-ALA ester (HAL) or apharmaceutically acceptable salt thereof; and b) exposing the inside ofsaid bladder to blue light having a fluence rate of 1.5 to 12.5 mW/cm².

In a preferred fifteenth embodiment, said blue light is provided at alight dose of 0.2 to 15.0 J/cm². In another preferred fifteenthembodiment, the inside of said bladder is exposed to white light havinga fluence rate of 3.0 to 22.0 mW/cm² and to blue light having a fluencerate of 1.5 to 12.5 mW/cm². In yet another preferred fifteenthembodiment, the inside of said bladder is exposed to white light havinga fluence rate of 3.0 to 22.0 mW/cm² and to blue light having a fluencerate of 1.5 to 12.5 mW/cm², wherein said white light is provided at alight dose of 0.4 to 26.5 J/cm² and said blue light at light dose of 0.2to 15.0 J/cm².

Various embodiments and preferred embodiments of this method ofneoadjuvant therapy for treating MIBC, i.e. embodiments 1-11, aredescribed above and can be used in this fifteenth embodiment.

In an alternative fourteenth embodiment, the invention provides acomposition comprising hexyl 5-ALA ester (HAL) or a pharmaceuticallyacceptable salt thereof for use in a method of neoadjuvant therapy fortreating MIBC, said method comprises a) instillation of the compositioninto the bladder of a patient in need of said treatment; and b) exposingthe inside of said bladder to blue light having a fluence rate of 1.5 to12.5 mW/cm²;

In a preferred alternative fifteenth embodiment, said blue light isprovided at a light dose of 0.2 to 15.0 J/cm². In another preferredalternative fifteenth embodiment, the inside of said bladder is exposedto white light having a fluence rate of 3.0 to 22.0 mW/cm² and to bluelight having a fluence rate of 1.5 to 12.5 mW/cm². In yet anotherpreferred alternative fifteenth embodiment, the inside of said bladderis exposed to white light having a fluence rate of 3.0 to 22.0 mW/cm²and to blue light having a fluence rate of 1.5 to 12.5 mW/cm², whereinsaid white light is provided at a light dose of 0.4 to 26.5 J/cm² andsaid blue light at light dose of 0.2 to 15.0 J/cm².

Various embodiments and preferred embodiments of the compositioncomprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable saltthereof for use in a method of neoadjuvant therapy for treating MIBC,i.e. embodiments 1-11, are described above and can be used in thisalternative fifteenth embodiment.

In a sixteenth embodiment, the invention provides a method of treatingMIBC, said method comprising a) neoadjuvant therapy and b) a subsequentcystectomy, the method of treating MIBC comprising a) instillation intothe bladder of a patient in need of said treatment of a compositioncomprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable saltthereof and exposing the inside of said bladder to blue light having afluence rate of 1.5 to 12.5 mW/cm²; and b) carrying out a cystectomy.

In a preferred sixteenth embodiment, said blue light is provided at alight dose of 0.2 to 15.0 J/cm². In another preferred sixteenthembodiment, the inside of said bladder is exposed to white light havinga fluence rate of 3.0 to 22.0 mW/cm² and to blue light having a fluencerate of 1.5 to 12.5 mW/cm². In yet another preferred fifteenthembodiment, the inside of said bladder is exposed to white light havinga fluence rate of 3.0 to 22.0 mW/cm² and to blue light having a fluencerate of 1.5 to 12.5 mW/cm², wherein said white light is provided at alight dose of 0.4 to 26.5 J/cm² and said blue light at light dose of 0.2to 15.0 J/cm².

Various embodiments and preferred embodiments of this method of treatingMIBC, i.e. embodiments 1-11, are described above and can be used in thissixteenth embodiment.

In an alternative sixteenth embodiment, the invention provides acomposition comprising hexyl 5-ALA ester (HAL) or a pharmaceuticallyacceptable salt thereof for use in a method of treating MIBC, saidmethod comprising a) neoadjuvant therapy and b) a subsequent cystectomy,the method of treating MIBC comprising a) instillation of thecomposition into the bladder of a patient in need of said treatment andexposing the inside of said bladder to blue light having a fluence rateof 1.5 to 12.5 mW/cm²; and b) carrying out a cystectomy.

In a preferred alternative sixteenth embodiment, said blue light isprovided at a light dose of 0.2 to 15.0 J/cm². In another preferredsixteenth embodiment, the inside of said bladder is exposed to whitelight having a fluence rate of 3.0 to 22.0 mW/cm² and to blue lighthaving a fluence rate of 1.5 to 12.5 mW/cm². In yet another preferredfifteenth embodiment, the inside of said bladder is exposed to whitelight having a fluence rate of 3.0 to 22.0 mW/cm² and to blue lighthaving a fluence rate of 1.5 to 12.5 mW/cm², wherein said white light isprovided at a light dose of 0.4 to 26.5 J/cm² and said blue light atlight dose of 0.2 to 15.0 J/cm².

Various embodiments and preferred embodiments of the compositioncomprising hexyl 5-ALA ester (HAL) or a pharmaceutically acceptable saltthereof for use in this method of treating MIBC, i.e. embodiments 1-11,are described above and can be used in this alternative sixteenthembodiment.

The time period between the neoadjuvant therapy of the inventiondescribed above and the cystectomy may vary but is preferably zero to 6weeks, e.g. zero to 4, 3, 2 or 1 week. “Zero” means that the cystectomyis carried out directly after the neoadjuvant therapy, i.e. after thelight irradiation/light exposure of the inside of the bladder isfinalized.

The neoadjuvant therapy can be carried out repeatedly prior to thecystectomy, e.g. two or more times, e.g. 3, 4, 5 or 6 times, with aperiod between the treatments of e.g. 4 days to 4 weeks, e.g. 1, 2 or 3weeks.

The neoadjuvant therapy can be carried out in combination withneoadjuvant radiotherapy and/or neoadjuvant chemotherapy.

Although being the gold standard for MIBC treatment and advocated inpatients with certain types of NMIBC, radical cystectomy only provides5-year survival in about 50% of patients. In order to improve theseunsatisfactory results, the use of neoadjuvant therapies has beenexplored since the 1980s.

Neoadjuvant radiotherapy has been used, down staging of the cancer afterradiotherapy takes about 4-6 weeks. However, a delay of surgery inpatients with locally advanced bladder cancer beyond 90 days has shownto cause a significant increase in extravesical disease (81 vs 52%).Neoadjuvant radiotherapy is not recommended according to the currentEuropean guidelines on MIBC since no data exist to support thatneoadjuvant radiotherapy for operable MIBC increases survival.

Neoadjuvant chemotherapy has many advantages including that chemotherapyis delivered at the earliest time-point, when the burden ofmicrometastatic disease is expected to be low; that tolerability ofchemotherapy is expected to be better before cystectomy rather thanafter; and that hypothetically patients with micrometastatic diseasemight respond to neoadjuvant therapy and reveal favorable pathologicalstatus determined mainly by negative lymph node status and negativesurgical margins. Neoadjuvant cisplatin-containing chemotherapy hasshown to significantly improve survival (5% absolute improvement insurvival at 5 years). However, as stated above, delayed cystectomy maycompromise the outcome in patients who are not sensitive to chemotherapyand generally, pre-operative anemia and neuropathy is more common inpatients receiving neoadjuvant chemotherapy prior to cystectomy. Thecurrent European guidelines on MIBC state that “ . . . neoadjuvantchemotherapy has its limitations regarding patient selection, currentdevelopment of surgical technique, and current chemotherapycombinations.” Hence, there is room for improvement of neoadjuvanttherapies for bladder cancer patients who need to undergo cystectomy.

The adjuvant or neoadjuvant therapies according to the method of theinvention have several advantages compared to neoadjuvant radiotherapy,(neo)adjuvant chemotherapy and (neo)adjuvant immunotherapy, wherenausea, vomiting, fatigue, anemia, damage to epithelial surfaces,intestinal discomfort/gastrointestinal stress, nephrotoxicity,neurotoxicity, swelling, depression of the immune system and infertilityare well-known and common adverse effects. In contrary thereto, the mostreported adverse reactions to HAL (in the form of Hexvix®/Cysview®) weretransient and mild to moderate in intensity. The most frequentlyreported adverse reactions from clinical studies with Hexvix®/Cysview®were bladder spasm, reported by 2.4% of the patients, dysuria by 1.8%,bladder pain by 1.7% and hematuria by 1.7% of the patients.

In addition, HAL has a highly favorable metabolic profile compared tochemotherapeutics, e.g. cisplatin. HAL interferes with the body's ownheme biosynthetic pathway and leads of accumulation of photoactiveporphyrins, particularly protoporphyrin IX (PpIX), which is the lastintermediate in heme synthesis. Since such photoactive porphyrins arecompounds which naturally occur in the body, there is a “naturalprocess” in the body for degrading (metabolizing) and excreting degradedheme.

EXAMPLES Example 1

Orthotopic Rat Bladder Tumor Model

A rat bladder carcinoma cell line was used in these experiments toestablish superficial bladder tumors in Female Fischer rats weighing150-175 g as described in François, et al., J. Urol. 190(2), 2013,731-736. The animals were used in the experiments 5 days after tumorcell inoculation.

PDT in Rat Bladders

Lyophilized HAL (in the form of Hexvix® powder) was dissolved in PBS toa final concentration of 2 mg/ml (8 mM). 0.5 ml of the solution wasinstilled into the rat bladder and was left in the bladder for about 1hour. After evacuation of the HAL solution, 0.5 ml of PBS was instilledinto the bladder and whole bladder irradiation with blue light at afluence rate of 3.5 or 7.0 mW/cm² was performed using a 170 mW Modulightlaser model ML 6500-405 delivering light at a wavelength of 401 nm,coupled to a fiber with a cylindrical diffuser (1×5 mm) modelRD05/500/800 (Medlight, Ecublens, Switzerland) placed in a centralposition in the bladder. Rats received a blue light dose of 4.0 J/cm²(fluence rate 3.5 mW/cm²) or 7.5 J/cm² (fluence rate 7.0 mW/cm²)

For control, no Hexvix was instilled and only blue light irradiation wascarried out at the aforementioned fluence rates/light doses.

Post PDT Protocol

The rats were sacrificed 48 hours after illumination by an overdose ofpentobarbital. Bladders were filled in with formaldehyde (4%), removedfrom the animals and transferred into a vials with formaldehyde (4%) fora minimum of 4 h. Then the bladder was macroscopically cut into 4 partsand fixed for 48 h. Following different cycles of dehydration withgradients of ethanol and xylene, the bladder tissue was included intoparaffin. Paraffin embedded sections of 5 μm were cut and used forhistology with haematoxylin/eosin staining.

Results

Bladders of animals in the control group (n=2 for each fluencerate/light dose) showed no inflammation (sign of a PDT effect) butpersistent and chorion infiltrating tumors for both fluence rates/lightdoses.

The bladders of 1 animal (50%) in the 3.5 mW/cm²/4 J/cm² group (n=2)showed no inflammation, persistent and chorion infiltrating tumors whilethe tumor in the bladder of another animal (50%) looked less compact andthe superficial layer of said tumor was destroyed.

Bladders of animals in the 7.0 mW/cm²/7.5 J/cm² group (n=2) showedincreased tissue thickness/inflammation (both signs of PDT effect) anddisintegrating/less compact tumor tissue.

Example 2

HAL/Blue Light Group:

A solution of HAL (Hexvix®) was instilled into the bladder of patientsthrough a catheter and was left in the bladder for about 1 hour. If thepatient could not retain the composition for about 1 hour, at leastabout 1 hour was allowed to pass from the instillation of Hexvix® to thestart of exposing the inside of the bladder to light. After evacuationof Hexvix®, a commercially available blue-light cystoscope was insertedinto the bladder and a TUR was carried out by exposing the inside of thebladder to white light for the visual inspection, subsequent blue lightexposure for fluorescence detection of bladder cancer lesions, resectionof the detected lesions under white light and monitoring of thecompleteness of the resection by use of blue light. Blue light wasprovided at a fluence rate of 1.5 to 12.5 mW/cm² and a light dose of 0.2to 15.0 J/cm² while light was provided at a fluence rate of 3.0 to 22.0mW/cm² and a light dose of 0.4 to 26.5 J/cm².

The resected bladder tumors were processed according to methods known inthe art and primary cell cultures were established from saidpatient-derived bladder tumor under appropriate conditions in culturemedium. No in vitro primary cell cultures could be established from saidresected bladder tumors.

No HAL/White Light Group:

A commercially available white light cystoscope was inserted into thebladder of patients and a TUR was carried out by exposing the inside ofthe bladder to white light for the visual inspection, detection ofbladder cancer lesions, resection of said lesions and monitoring of thecompleteness of the resection.

Resected bladder tumors were processed identically to those in theHAL/blue light group. In vitro primary cell cultures of such resectedbladder tumors could be established.

The fact that no in vitro primary cell cultures could be establishedfrom resected bladder tumors in the HAL/blue light patient group pointstowards a phototoxic effect, i.e. that tumor cells were killed in theapplied TUR procedure.

Example 3

A prospective, randomized, comparative, controlled phase III multicenterstudy was carried out in patients with non-muscle invasive papillarybladder cancer (NMIBC). The study population comprised 551 patientswhich were randomized into two groups (see below). The groups weresimilar in age, gender, race, bladder cancer history and priorintravesical therapy.

HAL Group:

271 patients. The method of the invention was carried out as follows: Asolution of HAL (Hexvix®) was instilled into the bladder of patientsthrough a catheter and was left in the bladder for about 1 hour. If thepatient could not retain the composition for about 1 hour, at leastabout 1 hour was allowed to pass from the instillation of Hexvix® to thestart of exposing the inside of the bladder to light.

After evacuation of Hexvix®, cystoscopy was carried out with acommercially available cystoscope (blue and white light). The inside ofthe bladder was first exposed to white light and visually assessed,followed by exposure to blue light to detect cancerous lesions in thebladder. Transurethral resection (TUR) of the detected lesions wascarried out under white light and completion of the resection wasassessed under blue light.

White Light Group:

280 patients. Cystoscopy and TUR of bladder cancer under white lightonly, no HAL.

Patients from both groups with histologically confirmed Ta or T1 lesionswere followed up by white light cystoscopy after 3, 6 and 9 months. Alltumor recurrences during the 9 months follow-up period werehistologically confirmed.

Comparison of Tumor Recurrence in Patients in the White Light Group andthe HAL Group According to the Invention

Tumor recurrence was observed during the 9 months follow-up period in157 of the 280 patients in the white light group (56.1%) and in 128 of271 patients in the HAL group (42.7%). This difference in tumorrecurrence rate is statistically significant and has been explained withimproved tumor detection and more complete resection in the HAL group(Stenzl et al., J Urol 184, 2010, 1907-1914).

Comparison of Tumor Recurrence in Patients Who Did/Did not Receive BCGIntravesical Treatment

50 patients in the HAL group (18.5%) and 55 patients in the white lightgroup (19.6%) received BCG treatment during the 9 months follow-upperiod. BCG (Bacillus Calmette-Guérin) is an immunotherapy agent for thetreatment of bladder cancer. It is usually repeatedly instilled into thebladder. Tumor recurrence rate in both patient groups were determinedand the results are displayed in Table 1

TABLE 1 Tumor recurrence rate by group and BCG treatment Group No BCGReceived BCG All White light 61.8% 32.7% 56.1% (n = 280) (139/225)(18/55) (157/280) HAL 49.3% 38.0% 47.2% (n = 271) (109/221) (19/50)(128/271)

As mentioned above, during the 9 months follow-up period in 157 of the280 patients in the white light group (56.1%) and in 128 of 271 patientsin the HAL group (42.7%) had confirmed tumor recurrence (Table 1, rightcolumn). This difference is mainly driven by the patients who did notreceive BCG (61.8% in the white light group versus 49.3% in the HALgroup). The difference in tumor recurrence for patients who received BCGbetween the groups is much less pronounced (32.7% in the white lightgroup versus 38.0% in the HAL group)

In the white light group the difference in recurrence rate between thepatients who received and who did not receive BCG treatment wasstatistically significant with a p-value<0.001 (32.7% versus 61.8%)which demonstrates the efficacy of BCG in preventing bladder cancerrecurrence.

In the HAL group, however, the efficacy of BCG treatment could not bedemonstrated, since the difference in recurrence rate between thepatients who received and who did not receive BCG was not statisticallysignificant (p-value=0.148, 38.0% versus 49.3%). This absence ofsignificant BCG effect is mainly due to pronounced reduced tumorrecurrence rate in patients who did not receive BCG (49.3% versus 61.8%)and this reduction in tumor recurrence rate could possibly be explainedby a therapeutic effect of HAL (HAL PDT effect) which results in theprevention of bladder cancer recurrence.

Comparison of Tumor Recurrence Rate in Patients Who Did/Did not ReceiveBCG and/or Mitomycin Intravesical Treatment

Mitomycin is a chemotherapeutic agent for the treatment of bladdercancer. It may be instilled after TUR (single instillation) to e.g.prevent tumor cell seeding, i.e. re-attachment to the bladder wall oftumor cells which were dislocated during resection. Mitomycin wasadministered after TUR to 16 patients in the HAL group (5.9%) and to 20patients in the white light group (7.1%).

Tumor recurrence rate in both patient groups were determined and theresults are displayed in Table 2

TABLE 2 Tumor recurrence rate by group and BCG and/or mitomycintreatment Received no BCG Received BCG Group and/or mitomycin and/ormitomycin All White light 63.1% 36.5% 56.1% (n = 280) (130/206) (27/74)(157/280) HAL 49.0% 41.5% 47.2% (n = 271) (101/206) (27/65) (128/271)

In the white light group the difference in recurrence rate between thepatients who received and who did not receive BCG and/or mitomycintreatment was statistically significant with a p-value<0.001 (36.5%versus 63.1%) which demonstrates the efficacy of BCG and/or mitomycin inpreventing bladder cancer recurrence.

In the HAL group, however, the efficacy of these treatments could not bedemonstrated, since the difference in recurrence rate between thepatients who received and who did not receive BCG and/or mitomycin wasnot statistically significant (p-value=0.291, 41.5% versus 49.0%). Thisabsence of significant BCG and/or mitomycin treatment effect is mainlydue to pronounced reduced tumor recurrence rate in patients who did notreceive BCG and/or mitomycin (49.0% versus 63.1%) and this reduction intumor recurrence rate could possibly be explained by a therapeuticeffect of HAL (HAL PDT effect) which results in the prevention ofbladder cancer recurrence.

Various embodiments of the invention are as follows:

Embodiment 1

Composition comprising hexyl 5-ALA ester (HAL) or a pharmaceuticallyacceptable salt thereof for use in a method of photodynamic therapy forbladder cancer, wherein said composition is instilled into the bladderof a patient in need of such treatment and the inside of said bladder isexposed to blue light having a fluence rate of 1.5 to 12.5 mW/cm².

Embodiment 2

Composition for use according to Embodiment 1, wherein the blue light isprovided at a light dose of 0.2 to 15.0 J/cm².

Embodiment 3

Composition for use according to Embodiment 1 or 2, wherein the insideof the bladder is exposed to blue light having a fluence rate of 2.5 to7.0 mW/cm².

Embodiment 4

Composition for use according to Embodiment 3, wherein the blue light isprovided at a light dose of 0.3 to 8.0 J/cm².

Embodiment 5

Composition for use according to any of Embodiments 1 to 4, wherein theinside of said bladder is further exposed to white light having afluence rate of 3.0 to 22.0 mW/cm².

Embodiment 6

Composition for use according to Embodiment 5, wherein said white lightis provided at a light dose of 0.4 to 26.5 J/cm².

Embodiment 7

Composition for use according to Embodiment 5, wherein said inside ofthe bladder is exposed to white light having a fluence rate of 5.0 to12.5 mW/cm².

Embodiment 8

Composition for use according to Embodiment 7, wherein said white lightis provided at a light dose of 0.6 to 15.0 J/cm².

Embodiment 9

Composition for use according to any of Embodiments 1 to 8, wherein saidcomposition is an aqueous solution of HAL, preferably a solution of HALin an aqueous buffer, more preferably a solution of HAL in a phosphatebuffer.

Embodiment 10

Composition for use according to Embodiment 9, wherein the pH of saidcomposition is in the range of 4.5 to 7.5, preferably in the range of5.7 to 7.2.

Embodiment 11

Composition for use according to any of Embodiments 1 to 10, whereinsaid composition is a solution of 2 mg/ml HAL hydrochloride in anaqueous buffer comprising disodium phosphate dehydrate, potassiumdihydrogen phosphate, sodium chloride, hydrochloric acid, sodiumhydroxide and water.

Embodiment 12

Composition for use according to any of Embodiments 5 to 11, whereinsaid inside of the bladder is first exposed to white light and then toblue light.

Embodiment 13

Composition for use according to any of Embodiments 1 to 12, wherein ablue-light cystoscope is used as a light source to provide and bluelight or said blue and white light.

Embodiment 14

Composition for use according to Embodiment 13, wherein said blue-lightcystoscope is a commercially available blue-light cystoscope.

Embodiment 15

Composition for use according to any of Embodiments 1 to 14, wherein theinside of the bladder is exposed to blue light or to blue and whitelight for a period of 2 to 20 minutes.

Embodiment 16

Composition for use according to any of Embodiments 1 to 15 for use in amethod of treating bladder cancer wherein said method of photodynamictherapy is used as adjuvant therapy.

Embodiment 17

Composition for use according to Embodiment 16, wherein said bladdercancer is NMIBC and said method of photodynamic therapy issimultaneously carried out with a transurethral resection of NMIBC.

Embodiment 18

Composition for use according to Embodiment 16, wherein said bladdercancer is NMIBC and said method of photodynamic therapy is carried in apatient having undergone transurethral resection of NMIBC.

Embodiment 19

Composition for use according to Embodiments 16-18, wherein said methodof photodynamic therapy replaces or partially replaces other adjuvanttherapies.

Embodiment 20

Composition for use according to Embodiment 19, wherein said otheradjuvant therapies are chemotherapy and/or immunotherapy, preferably BCGtreatment.

Embodiment 21

Composition for use according to Embodiment 19, wherein said method ofphotodynamic therapy is carried out in BCG refractory patients.

Embodiment 22

Composition for use according to any of Embodiments 1 to 15 for use in amethod of treating bladder cancer wherein said method of photodynamictherapy is used as neoadjuvant therapy.

Embodiment 23

Composition for use according to Embodiment 22, wherein said bladdercancer is MIBC.

Embodiment 24

Composition for use according to Embodiment 23, wherein said method ofphotodynamic therapy is carried out prior to a cystectomy.

Embodiment 25

Composition for use according to Embodiment 24, wherein the cystectomyis carried out directly after the method of photodynamic therapy.

Embodiment 26

Method of photodynamic therapy for bladder cancer comprising theinstillation into the bladder of a patient in need of such treatment ofa composition comprising hexyl 5-ALA ester (HAL) or a pharmaceuticallyacceptable salt thereof and exposing the inside of said bladder to bluelight having a fluence rate of 1.5 to 12.5 mW/cm².

Embodiment 27

Method according to Embodiment 26, wherein the blue light is provided ata light dose of 0.2 to 15.0 J/cm².

Embodiment 28

Method according to Embodiment 26 or 27, wherein the inside of thebladder is exposed to blue light having a fluence rate of 2.5 to 7.0mW/cm².

Embodiment 29

Method according to Embodiment 28, wherein the blue light is provided ata light dose of 0.3 to 8.0 J/cm².

Embodiment 30

Method according to any of Embodiments 26 to 29, wherein the inside ofsaid bladder is further exposed to white light having a fluence rate of3.0 to 22.0 mW/cm².

Embodiment 31

Method according to Embodiment 30, wherein said white light is providedat a light dose of 0.4 to 26.5 J/cm².

Embodiment 32

Method according to Embodiment 30, wherein said inside of the bladder isexposed to white light having a fluence rate of 5.0 to 12.5 mW/cm².

Embodiment 33

Composition for use according to Embodiment 32, wherein said white lightis provided at a light dose of 0.6 to 15.0 J/cm².

Embodiment 34

Method according to any of Embodiments 26 to 33, wherein saidcomposition is an aqueous solution of HAL, preferably a solution of HALin an aqueous buffer, more preferably a solution of HAL in a phosphatebuffer.

Embodiment 35

Method according to Embodiment 34, wherein the pH of said composition isin the range of 4.5 to 7.5, preferably in the range of 5.7 to 7.2.

Embodiment 36

Method according to any of Embodiments 26 to 35, wherein saidcomposition is a solution of 2 mg/ml HAL hydrochloride in an aqueousbuffer comprising disodium phosphate dehydrate, potassium dihydrogenphosphate, sodium chloride, hydrochloric acid, sodium hydroxide andwater.

Embodiment 37

Method according to any of Embodiments 30 to 36, wherein said inside ofthe bladder is first exposed to white light and then to blue light.

Embodiment 38

Method according to any of Embodiments 26 to 37, wherein a blue-lightcystoscope is used as a light source to provide and blue light or saidblue and white light.

Embodiment 39

Method according to Embodiment 38, wherein said blue-light cystoscope isa commercially available blue-light cystoscope.

Embodiment 40

Method according to any of Embodiments 26 to 39, wherein the inside ofthe bladder is exposed to blue light or to blue and white light for aperiod of 2 to 20 minutes.

Embodiment 41

Method according to any of Embodiments 26 to 40 for use in a method oftreating bladder cancer wherein said method of photodynamic therapy isused as adjuvant therapy.

Embodiment 42

Method according to Embodiment 41, wherein said bladder cancer is NMIBCand said method of photodynamic therapy is simultaneously carried outwith a transurethral resection of NMIBC.

Embodiment 43

Method according to Embodiment 41, wherein said bladder cancer is NMIBCand said method of photodynamic therapy is carried in a patient havingundergone transurethral resection of NMIBC.

Embodiment 44

Method according to Embodiments 41 to 43, wherein said method ofphotodynamic therapy replaces or partially replaces other adjuvanttherapies.

Embodiment 45

Method according to Embodiment 44, wherein said other adjuvant therapiesare chemotherapy and/or immunotherapy, preferably BCG treatment.

Embodiment 46

Method according to Embodiment 44, wherein said method of photodynamictherapy is carried out in BCG refractory patients.

Embodiment 47

Method according to any of Embodiments 26 to 40 for use in a method oftreating bladder cancer wherein said method of photodynamic therapy isused as neoadjuvant therapy.

Embodiment 48

Method according to Embodiment 47, wherein said bladder cancer is MIBC.

Embodiment 49

Method according to Embodiment 48, wherein said method of photodynamictherapy is carried out prior to a cystectomy.

Embodiment 50

Method according to Embodiment 49, wherein the cystectomy is carried outdirectly after the method of photodynamic therapy.

The invention claimed is:
 1. A method of photodynamic therapy forbladder cancer comprising the instillation into the bladder of a patientin need of such treatment of a composition in the form of a solution of2 mg/ml hexyl 5-ALA ester (HAL) hydrochloride in an aqueous buffercomprising disodium phosphate dehydrate, potassium dihydrogen phosphate,sodium chloride, hydrochloric acid, sodium hydroxide and water andexposing the inside of said bladder to blue light having a fluence rateof 1.5 to 12.5 mW/cm² and wherein the blue light is provided at a lightdose of 0.2 to 15.0 J/cm².
 2. The method according to claim 1, whereinthe inside of the bladder is exposed to blue light having a fluence rateof 2.5 to 7.0 mW/cm².
 3. The method according to claim 2, wherein theblue light is provided at a light dose of 0.3 to 8.0 J/cm².
 4. Themethod according to claim 1, wherein the blue light is provided at alight dose of 0.3 to 8.0 J/cm².
 5. The method according to claim 1,wherein the inside of said bladder is further exposed to white lighthaving a fluence rate of 3.0 to 22.0 mW/cm².
 6. The method according toclaim 5, wherein said white light is provided at a light dose of 0.4 to26.5 J/cm².
 7. The method according to claim 5, wherein said inside ofthe bladder is exposed to white light having a fluence rate of 5.0 to12.5 mW/cm².
 8. The method according to claim 5, wherein said whitelight is provided at a light dose of 0.6 to 15.0 J/cm².
 9. The methodaccording to claim 8, wherein said white light is provided at a lightdose of 0.6 to 15.0 J/cm².
 10. The method according to claim 5, whereinsaid inside of the bladder is first exposed to white light and then toblue light.
 11. The method according to claim 5, wherein a blue-lightcystoscope is used as a light source to provide said blue light and saidwhite light.
 12. The method according to claim 5, wherein the inside ofthe bladder is exposed to blue light and white light for a period of 2to 20 minutes.
 13. The method according to claim 5, wherein said methodof photodynamic therapy is used as adjuvant therapy in the treatment ofbladder cancer.
 14. The method according to claim 13, wherein saidbladder cancer is NMIBC and said method of photodynamic therapy issimultaneously carried out with a transurethral resection of NMIBC. 15.The method according to claim 13, wherein said bladder cancer is NMIBCand said method of photodynamic therapy is carried in a patient havingundergone transurethral resection of NMIBC.
 16. The method according toclaim 13, wherein said method of photodynamic therapy replaces orpartially replaces other adjuvant therapies.
 17. The method according toclaim 16, wherein said other adjuvant therapies are chemotherapy and/orimmunotherapy.
 18. The method according to claim 17, wherein said otheradjuvant therapy is BCG treatment.
 19. The method according to claim 5,wherein said method of photodynamic therapy is carried out in BCGrefractory patients.
 20. The method according claim 5, wherein saidmethod of photodynamic therapy is used as neoadjuvant therapy in amethod of treating bladder cancer.
 21. The method according to claim 20,wherein said bladder cancer is MIBC.
 22. The method according to claim1, wherein said composition is an aqueous solution of HAL.
 23. Themethod according to claim 22, wherein said composition is a solution ofHAL in an aqueous buffer.
 24. The method according to claim 22, whereinsaid composition is a solution of HAL in a phosphate buffer.
 25. Themethod according to claim 22, wherein the pH of said composition is inthe range of 4.5 to 7.5.
 26. The method according to claim 1, wherein ablue-light cystoscope is used as a light source to provide said bluelight.
 27. The method according to claim 26, wherein said blue-lightcystoscope is a commercially available blue-light cystoscope.
 28. Themethod according to claim 1, wherein the inside of the bladder isexposed to blue light for a period of 2 to 20 minutes.
 29. The methodaccording to claim 1, wherein said method of photodynamic therapy isused as adjuvant therapy in the treatment of bladder cancer.
 30. Themethod according to claim 29, wherein said bladder cancer is NMIBC andsaid method of photodynamic therapy is simultaneously carried out with atransurethral resection of NMIBC.
 31. The method according to claim 29,wherein said bladder cancer is NMIBC and said method of photodynamictherapy is carried in a patient having undergone transurethral resectionof NMIBC.
 32. The method according to claim 29, wherein said method ofphotodynamic therapy replaces or partially replaces other adjuvanttherapies.
 33. The method according to claim 32, wherein said otheradjuvant therapies are chemotherapy and/or immunotherapy.
 34. The methodaccording to claim 33, wherein said other adjuvant therapy is BCGtreatment.
 35. The method according to claim 1, wherein said method ofphotodynamic therapy is carried out in BCG refractory patients.
 36. Themethod according claim 1, wherein said method of photodynamic therapy isused as neoadjuvant therapy in a method of treating bladder cancer. 37.The method according to claim 36, wherein said bladder cancer is MIBC.